Brazil’s dengue vaccine remains effective for up to 5 years
A new study published by the Butantan Institute shows that the Brazilian dengue vaccine remains effective for at least five years after administration.
The Butantan-DV vaccine was approved by Brazil’s drug authority Anvisa in November last year and has begun to be administered to health care professionals in various parts of the country.
During this period, no vaccinated individuals developed severe dengue or required hospitalization due to the disease. As a result, the vaccine’s efficacy against severe forms of the disease or infection accompanied by warning signs stood at 80.5 percent.
The results also varied according to age, with greater efficacy among adults and adolescents than among children.
For this reason, Anvisa registered Butantan-DV only for people aged 12 to 59, even though the vaccine was also tested on children aged two and older.
Butantan’s Medical Director Fernanda Boulos noted that this result is positive not only because it confirms the vaccine’s efficacy, but also because it demonstrates the efficiency of the single-dose regimen. The vaccine produced by the institute is the first in the world against dengue fever to be administered in a single dose.
“For vaccines that require two or more doses, we have several data showing that many people do not follow up to complete the regimen. So, this demonstration that a single dose maintains high protection is critical,” she said.
Safety
The results of the long-term Butantan-DV study were published Wednesday (Mar. 4) in the journal Nature Medicine and explain that the vaccine was generally well tolerated and no long-term safety concerns were observed.
The data were obtained after monitoring over 16 thousand patients, of whom about 10 thousand received the vaccine and almost 6 thousand received a placebo to form a comparison group.
“In strategic terms, we need to have national research that can get us these cutting-edge, effective, and safe products. It makes it easier for us to supply our national immunization program and is also an asset for negotiating with other countries,” says Juarez Cunha, director of the Brazilian Society of Immunizations.
Boulos confirms that the absolute priority is to supply Brazil’s national health care network, the SUS. However, once national demand has been met, Butantan Institute, linked to the state of São Paulo, should negotiate the sale of doses to other countries, especially in Latin America, which has also suffered from epidemics of the disease.
